Fastening devices for sewing machine attachments and the like



March 17, 1959 J. P. ENOS 2,877,728

FASTENING DEVICES FOR SEWING MACHINE ATTACHMENTS AND THE LIKE Filed April 12, 1956 F i g 5 INVENTOR.

W/TNESS John EH05 BY k W ATTORNEY United 1;;

FASTENING DEVICES FOR SEWING MACHINE ATTACHMENTS AND THE LIKE John P. Enos, Union, N. 1., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application April 12, 1956, Serial No. 577,685

4 Claims. (Cl. 112-260) This invention relates to a device for securing an attachment or the like to a sewing machine frame, and more particularly, to an improved device for maintaining one or more attachment fastening screws captive on the attachment.

It is an object of this invention to provide an attachment fastening device carried as a part of the attachment and capable of securing the attachment to any one of a wide variety of sewing machines.

It is also an object of this invention to provide an attachment fastening device adapted on mere assembly of the parts to maintain one or more attachment fastening screws captive on the attachment.

With the above and other objects and advantages in view as will hereinafter appear, this invention comprises the devices, combinations, and arrangement of parts hereinafter described and illustrated in the accompanying drawings of a preferred embodiment in which:

Fig. 1 represents a top plan view of a feed cover-plate attachment for a sewing machine attached by the securing device of this invention to a sewing machine work sup- P Fig. 2 represents an enlarged top plan view of the shank portion of the feed cover-plate of Fig. 1 with the rivet and securing screws in section;

Fig. 3 is an enlarged cross sectional view, taken substantially along line 33 of Fig. 1;

Fig. 4 is an enlarged cross sectional view, taken substantially along line 4-4 of Fig. 1; and

Fig. 5 represents a perspective view of the fastening screw retainer and a fastening screw prior to being assembled.

Referring more particularly to Fig. 1, this invention is illustrated as it is applied to a device for securing a feed cover-plate, indicated generally as 11, to the bed 12 of a sewing machine, a fragment of which is illustrated in Fig. 1. As is well known in the art, a feed cover-plate is a sewing machine attachment particularly useful for darning or embroidery work in that it provides a worksupporting platform 13 which is raised sufiiciently above the level of the top of the bed 12 as completely to cover and render ineffective the conventional work feeding instrumentalities of the sewing machine. The work-supporting platform of the feed cover-plate is formed with an aperture 14 through which the sewing machine needle operates. The platform is also formed with an enlarged opening 15 to accommodate the piercer of a conventional hemstitching attachment.

The feed cover-plate is secured to the sewing machine bed, making use of one or more tapped holes 16 customarily formed in the bed for the purpose of attachment fastening. An extension 17 provided on the feed cover-plate is formed with an elongated opening 18 adapted to overlie the tapped holes 16 in the machine bed when the feed cover-plate is properly positioned on the bed. The elongated opening 18 is formed with sufficient width to accommodate, without interference, the threaded shank portions 19 of the fastening screws 20. Each of the screws 20 is formed with an enlarged head 21 and between the head and the threaded shank portion there is formed a narrowed neck 22.

It is a feature of this invention that the fastening screws are held captive on the attachment. Thus, the screws may not be removed completely from the attachment and therefore cannot become lost or misplaced. Limited movement of the screws is possible both transversely, for the purpose of alignment of the screws with the tapped holes, and also axially, as in threading and unthreading the screws in the tapped holes.

The screws 20 are held captive one in each of the arms 23, 24 of a retainer member 25 which is preferably made of spring steel so that the arms 23, 24 may flex readily and independently of each other. As best illustrated in Figs. 2 and 5, each of the arms 23 and 24 is provided with a keyhole shaped aperture providing at one extremity an enlarged portion 26 slightly larger than the diameter of the threaded shank 19 of the fastening screw 20 and at the opposite extremity an elongated slot portion 27 having a width smaller than the diameter of the threaded shank 19 of the fastening screw and larger than the diameter of the narrowed neck portion 22 of the fastening screw. The keyhole shaped apertures may be of identical conformation. However, it is preferable that the elongated slot portions 27 extend in angular relation one with the other for the purpose of adjusting the spacing between the fastening screws 20 as will be described hereinafter.

The retainer member 25 is also formed with a slot 28 disposed to extend transversely of the elongated slot portions 27 of the keyhole shaped apertures. A shouldered rivet 29 fixed in the attachment extension and extending through the slot 28 provides a slidingly pivotal connection between the retainer member and the attachment.

The fastening device of this invention is assembled by first inserting the threaded shank portions 19 of the fastening screws into the enlarged portions 26 of the keyhole shaped apertures in theretainer member 25, thus bringing the narrowed neck portions 22 of the fastening screws into register with the elongated slot portions 27 of the keyhole shaped apertures. The screws are then shifted toward the free extremities of the arms 23, 24, the screws being confined on the arms by the side walls of the elongated slots 27. The retainer member is then placed upon the extension 17 of the feed cover-plate with the screws 20 in the elongated opening 18 of the extension. The assembly is then completed by inserting the rivet 29 through the slot 28 and into its hole in the extension, following which the rivet is set. As illustrated clearly in Fig. 2, the rivet is disposed so as to position the enlarged portions 26 of the keyhole shaped apertures in the retainer member to overlie the attachment extension 17 and the elongated slot portions 27 over the elongated opening 18 of the attachment extension. The positioning of the enlarged portions 26 of the keyhole shaped apertures directly over the attachment extension prevents the fastening screws from being shifted along the slot portions 27 into the enlarged portions 26 and thus prevents removal of the screws 20 from the attachment.

It will be appreciated that this construction provides a captive fastening screw arrangement effective upon mere assembly of the parts without the necessity, common in prior devices of this nature, of one or more steps of mutilation or deformation of a part in order to insure captivity of the screw.

The slidingly pivotal connection between the retainer member 25 and the attachment provides not only for adjustment of the position of the fastening screws along the opening 18 of the attachment but also by virtue of the angular arrangement of the keyhole shaped apertures in the-arms 23, 24-of the retainer member 25, slight turning adjustment of the retainer member about the rivet 29 will effect a change in the spacing of the fastening screws. By these adjustments the attachment may be' fastened conveniently to any one of'a' variety of sewing machines despite variations in the location and spacing of the tapped fastening screw holes therein.

Having thus set forth the nature of the invention, what I claim herein is:

1. A device for fastening an attachment to'a sewing machine frame having a tapped hole formed therein, comprising a fastening'screw having a threaded shank formed with a narrowed neck portion, said attachment being formed with an elongated opening through which the threaded portion of said fastening screw extends, a fiat resilient arm formed with a slot having a portion of a width substantially smaller than the diameter of the threaded shank of said fastening screw and larger than the diameter of said narrowed neck' portion, said fastening screw extending through the slot in said resilient arm with said slot embracing said narrowed neck portion of the screw, and means securing said resilient arm to said attachment with said resilient arm spanning the elongated opening in said attachment and with the slot in said arm overlying the elongated opening in said attachment and a portion of said attachment.

2. A device for fastening an attachment to a sewing machine frame having a tapped hole formed therein, comprising a fastening screw having athreaded shank formed with a narrowed neck portion, said attachment being formed with an elongated opening through which the threaded portion of said fastening screw extends, a flexible screw-retaining member formed with a slot having a portion of'a width smaller than the diameter of the threaded shank of said fastening screw and larger than the diameter of said narrowed neck portion and an enlarged extremity providing sufficient clearance to accommodate insertion of the threaded shank of said fastening screw, and means securing said flexible screw-retaining member to said attachment with only the narrow portion of said slotoverlying the elongated opening in said attachment.

3. A device for fastening an attachment to a sewing machine frame having a pair of tapped holes formed 4 therein, comprising a pair of fastening screws each having a threaded shank formed with a narrowed neck portion, said attachment being formed with an elongated opening through which the threaded portions of said fastening screws extend, a fastening screw retainer formed with a pair of resilient arms of which each is formed with a slot having a width smaller than the diameter of the threaded fastening screw shank and larger than the diameter of said narrowed neck portion thereof, said fastening screws extending one through the slot in each of said pair of resilient arms with said slots embracing the narrowed neck portion of each of said screws, and means forsecuring said fastening screw retainer to said attachment with said resilient arms spanning said elongated opening and the slotin each of said resilient arms overlying the elongated opening in said attachment and extending transversely thereof.

4. A device for fastening an attachment to a sewing machine frame having a pair of tapped holes formed therein, comprising-a pair of fastening screws each having a threaded shank formed with a narrowed neck portion, said attachment being formed with an opening through which the threaded portions of said fastening screws extend, and means maintaining said fastening screws captive in said opening including a fastening screw retainer formed with a pair of resilient arms, each of said resilient arms being formed with a clearance aperture providing for the insertion of the shank portion of one of said fastening screws and each formed with a slot opening into said aperture and having a width smaller than the diameter of the threaded fastening screw shank and larger than the diameter of said narrowed neck portion of said screw, said-slots being arranged to extend in angular-relation one with the other, and means slidably pivoting said fastening screw retainer to said attachment with the slots in said retainer overlying the opening in said attachment and the clearance apertures in said retainer overlying said attachment.

References Cited in the file of this patent UNITED-STATES PATENTS 1,262,114 Smallbone Apr. 9, 1918 1,491,394 Griffith et al Apr. 22, 1924 2,593,864 Enos Apr. 22, 1952 

